XML 30 R37.htm IDEA: XBRL DOCUMENT v2.4.1.9

Summary of Significant Accounting Policies Balancing and Memorandum Accounts (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Schedule of Balancing and Memorandum Accounts [Line Items]
Memorandum Account, Net	$ (1,377)sjw_MemorandumAccountNet	$ (1,896)sjw_MemorandumAccountNet	$ (1,887)sjw_MemorandumAccountNet	$ 5,739sjw_MemorandumAccountNet
Memorandum Account, Revenue Increase (Reduction)	341sjw_MemorandumAccountRevenueIncreaseReduction	869sjw_MemorandumAccountRevenueIncreaseReduction	(2,832)sjw_MemorandumAccountRevenueIncreaseReduction
Memorandum Account, Refunds (Collections)	178sjw_MemorandumAccountRefundsCollections	(878)sjw_MemorandumAccountRefundsCollections	(4,794)sjw_MemorandumAccountRefundsCollections
Balancing Account, Net	48,438sjw_BalancingAccountNet	9,585sjw_BalancingAccountNet	5,436sjw_BalancingAccountNet	0sjw_BalancingAccountNet
Balancing Account, Revenue Increase (Reduction)	41,657sjw_BalancingAccountRevenueIncreaseReduction	4,149sjw_BalancingAccountRevenueIncreaseReduction	5,436sjw_BalancingAccountRevenueIncreaseReduction
Balancing Account, Refunds (Collections)	(2,804)sjw_BalancingAccountRefundsCollections	0sjw_BalancingAccountRefundsCollections	0sjw_BalancingAccountRefundsCollections
Balancing and memorandum accounts, including interest	47,061sjw_BalancingAndMemorandumAccountNet	7,689sjw_BalancingAndMemorandumAccountNet	3,549sjw_BalancingAndMemorandumAccountNet	5,739sjw_BalancingAndMemorandumAccountNet
Balancing and Memorandum Account, Revenue Increase (Reduction), Net	41,998sjw_BalancingandMemorandumAccountRevenueIncreaseReductionNet	5,018sjw_BalancingandMemorandumAccountRevenueIncreaseReductionNet	2,604sjw_BalancingandMemorandumAccountRevenueIncreaseReductionNet
Balancing and Memorandum Account, Refunds (Collections), Net	(2,626)sjw_BalancingandMemorandumAccountRefundsCollections	(878)sjw_BalancingandMemorandumAccountRefundsCollections	(4,794)sjw_BalancingandMemorandumAccountRefundsCollections
Other Regulatory Assets [Member]
Schedule of Balancing and Memorandum Accounts [Line Items]
Balancing Account, Net	1,736sjw_BalancingAccountNet / us-gaap_RegulatoryAssetAxis = sjw_OtherRegulatoryAssetsMember	2,229sjw_BalancingAccountNet / us-gaap_RegulatoryAssetAxis = sjw_OtherRegulatoryAssetsMember	369sjw_BalancingAccountNet / us-gaap_RegulatoryAssetAxis = sjw_OtherRegulatoryAssetsMember
Balancing Account, Revenue Increase (Reduction)	(447)sjw_BalancingAccountRevenueIncreaseReduction / us-gaap_RegulatoryAssetAxis = sjw_OtherRegulatoryAssetsMember	1,860sjw_BalancingAccountRevenueIncreaseReduction / us-gaap_RegulatoryAssetAxis = sjw_OtherRegulatoryAssetsMember	369sjw_BalancingAccountRevenueIncreaseReduction / us-gaap_RegulatoryAssetAxis = sjw_OtherRegulatoryAssetsMember
Balancing Account, Refunds (Collections)	(46)sjw_BalancingAccountRefundsCollections / us-gaap_RegulatoryAssetAxis = sjw_OtherRegulatoryAssetsMember	0sjw_BalancingAccountRefundsCollections / us-gaap_RegulatoryAssetAxis = sjw_OtherRegulatoryAssetsMember	0sjw_BalancingAccountRefundsCollections / us-gaap_RegulatoryAssetAxis = sjw_OtherRegulatoryAssetsMember
2012 General Rate Case True-up [Member]
Schedule of Balancing and Memorandum Accounts [Line Items]
Balancing Account, Net	44,400sjw_BalancingAccountNet / us-gaap_RegulatoryAssetAxis = sjw_A2012GeneralRateCaseTrueupMember	0sjw_BalancingAccountNet / us-gaap_RegulatoryAssetAxis = sjw_A2012GeneralRateCaseTrueupMember	0sjw_BalancingAccountNet / us-gaap_RegulatoryAssetAxis = sjw_A2012GeneralRateCaseTrueupMember	0sjw_BalancingAccountNet / us-gaap_RegulatoryAssetAxis = sjw_A2012GeneralRateCaseTrueupMember
Balancing Account, Revenue Increase (Reduction)	46,456sjw_BalancingAccountRevenueIncreaseReduction / us-gaap_RegulatoryAssetAxis = sjw_A2012GeneralRateCaseTrueupMember	0sjw_BalancingAccountRevenueIncreaseReduction / us-gaap_RegulatoryAssetAxis = sjw_A2012GeneralRateCaseTrueupMember	0sjw_BalancingAccountRevenueIncreaseReduction / us-gaap_RegulatoryAssetAxis = sjw_A2012GeneralRateCaseTrueupMember
Balancing Account, Refunds (Collections)	(2,056)sjw_BalancingAccountRefundsCollections / us-gaap_RegulatoryAssetAxis = sjw_A2012GeneralRateCaseTrueupMember	0sjw_BalancingAccountRefundsCollections / us-gaap_RegulatoryAssetAxis = sjw_A2012GeneralRateCaseTrueupMember	0sjw_BalancingAccountRefundsCollections / us-gaap_RegulatoryAssetAxis = sjw_A2012GeneralRateCaseTrueupMember
Pension Balancing Account [Member]
Schedule of Balancing and Memorandum Accounts [Line Items]
Balancing Account, Net	1,412sjw_BalancingAccountNet / us-gaap_RegulatoryAssetAxis = sjw_PensionBalancingAccountMember	9,734sjw_BalancingAccountNet / us-gaap_RegulatoryAssetAxis = sjw_PensionBalancingAccountMember	6,657sjw_BalancingAccountNet / us-gaap_RegulatoryAssetAxis = sjw_PensionBalancingAccountMember	0sjw_BalancingAccountNet / us-gaap_RegulatoryAssetAxis = sjw_PensionBalancingAccountMember
Balancing Account, Revenue Increase (Reduction)	(7,705)sjw_BalancingAccountRevenueIncreaseReduction / us-gaap_RegulatoryAssetAxis = sjw_PensionBalancingAccountMember	3,077sjw_BalancingAccountRevenueIncreaseReduction / us-gaap_RegulatoryAssetAxis = sjw_PensionBalancingAccountMember	6,657sjw_BalancingAccountRevenueIncreaseReduction / us-gaap_RegulatoryAssetAxis = sjw_PensionBalancingAccountMember
Balancing Account, Refunds (Collections)	(617)sjw_BalancingAccountRefundsCollections / us-gaap_RegulatoryAssetAxis = sjw_PensionBalancingAccountMember	0sjw_BalancingAccountRefundsCollections / us-gaap_RegulatoryAssetAxis = sjw_PensionBalancingAccountMember	0sjw_BalancingAccountRefundsCollections / us-gaap_RegulatoryAssetAxis = sjw_PensionBalancingAccountMember
Water supply balancing accounts [Member]
Schedule of Balancing and Memorandum Accounts [Line Items]
Balancing Account, Net	890sjw_BalancingAccountNet / us-gaap_RegulatoryAssetAxis = sjw_WaterSupplyBalancingAccountsMember	(2,378)sjw_BalancingAccountNet / us-gaap_RegulatoryAssetAxis = sjw_WaterSupplyBalancingAccountsMember	(1,590)sjw_BalancingAccountNet / us-gaap_RegulatoryAssetAxis = sjw_WaterSupplyBalancingAccountsMember	0sjw_BalancingAccountNet / us-gaap_RegulatoryAssetAxis = sjw_WaterSupplyBalancingAccountsMember
Balancing Account, Revenue Increase (Reduction)	3,353sjw_BalancingAccountRevenueIncreaseReduction / us-gaap_RegulatoryAssetAxis = sjw_WaterSupplyBalancingAccountsMember	(788)sjw_BalancingAccountRevenueIncreaseReduction / us-gaap_RegulatoryAssetAxis = sjw_WaterSupplyBalancingAccountsMember	(1,590)sjw_BalancingAccountRevenueIncreaseReduction / us-gaap_RegulatoryAssetAxis = sjw_WaterSupplyBalancingAccountsMember
Balancing Account, Refunds (Collections)	$ (85)sjw_BalancingAccountRefundsCollections / us-gaap_RegulatoryAssetAxis = sjw_WaterSupplyBalancingAccountsMember	$ 0sjw_BalancingAccountRefundsCollections / us-gaap_RegulatoryAssetAxis = sjw_WaterSupplyBalancingAccountsMember	$ 0sjw_BalancingAccountRefundsCollections / us-gaap_RegulatoryAssetAxis = sjw_WaterSupplyBalancingAccountsMember

X

- Definition

This represents the under-collection or over-collection associated with expense changes and the revenue authorized by the CPUC to offset those expense changes. Pursuant to Section 792.5 of the California Public Utilities Code, a balancing account must be maintained for expense items for which revenue offsets have been authorized. Since the amounts in the balancing accounts must be approved by the CPUC before they can be incorporated into rates, the Company does not recognize balancing accounts in its revenue until CPUC approval occurs. It is typical for the CPUC to incorporate any over-collected and/or under-collected balances in balancing accounts into customer rates at the time rate decisions are made as part of the Company’s general rate case proceedings by assessing temporary surcredits and/or surcharges.

+ References

No definition available.

+ Details

Name:	sjw_BalancingAccountNet
Namespace Prefix:	sjw_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Balancing Account, Refunds (Collections)

+ References

No definition available.

+ Details

Name:	sjw_BalancingAccountRefundsCollections
Namespace Prefix:	sjw_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Balancing Account, Revenue Increase (Reduction)

+ References

No definition available.

+ Details

Name:	sjw_BalancingAccountRevenueIncreaseReduction
Namespace Prefix:	sjw_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Balancing and Memorandum Account, Net

+ References

No definition available.

+ Details

Name:	sjw_BalancingAndMemorandumAccountNet
Namespace Prefix:	sjw_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Balancing and Memorandum Account, Refunds (Collections)

+ References

No definition available.

+ Details

Name:	sjw_BalancingandMemorandumAccountRefundsCollections
Namespace Prefix:	sjw_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Balancing and Memorandum Account, Revenue Increase (Reduction), Net

+ References

No definition available.

+ Details

Name:	sjw_BalancingandMemorandumAccountRevenueIncreaseReductionNet
Namespace Prefix:	sjw_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

This represents the memorandum accounts that track under-collection or over-collection for approved activities as directed by the CPUC. Rate recovery for these memorandum accounts is generally allowed in the next general rate cases.

+ References

No definition available.

+ Details

Name:	sjw_MemorandumAccountNet
Namespace Prefix:	sjw_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Definition

Memorandum Account, Refunds (Collections)

+ References

No definition available.

+ Details

Name:	sjw_MemorandumAccountRefundsCollections
Namespace Prefix:	sjw_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Memorandum Account, Revenue Increase (Reduction)

+ References

No definition available.

+ Details

Name:	sjw_MemorandumAccountRevenueIncreaseReduction
Namespace Prefix:	sjw_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Details

Name:	sjw_ScheduleofBalancingandMemorandumAccountsLineItems
Namespace Prefix:	sjw_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Details

Name:	us-gaap_RegulatoryAssetAxis=sjw_A2012GeneralRateCaseTrueupMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_RegulatoryAssetAxis=sjw_OtherRegulatoryAssetsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_RegulatoryAssetAxis=sjw_PensionBalancingAccountMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_RegulatoryAssetAxis=sjw_WaterSupplyBalancingAccountsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: